In Reasons and Persons, Parfit (1984) posed a challenge: provide a satisfying normative account that solves the Non-Identity Problem, avoids the Repugnant and Absurd Conclusions, and solves the Mere-Addition Paradox. In response, some have suggested that we look toward person-affecting views of morality for a solution. But the person-affecting views that have been offered so far have been unable to satisfy Parfit's four requirements, and these views have been subject to a number of independent complaints. This paper describes a person-affecting (...) account which meets Parfit's challenge. The account satisfies Parfit's four requirements, and avoids many of the criticisms that have been raised against person-affecting views. (shrink)

Arrhenius’s impossibility theorems purport to demonstrate that no population axiology can satisfy each of a small number of intuitively compelling adequacy conditions. However, it has recently been pointed out that each theorem depends on a dubious assumption: Finite Fine-Grainedness. This assumption states that there exists a finite sequence of slight welfare differences between any two welfare levels. Denying Finite Fine-Grainedness makes room for a lexical population axiology which satisfies all of the compelling adequacy conditions in each theorem. Therefore, Arrhenius’s theorems (...) fail to prove that there is no satisfactory population axiology. In this paper, I argue that Arrhenius’s theorems can be repurposed. Since all of our population-affecting actions have a non-zero probability of bringing about more than one distinct population, it is population prospect axiologies that are of practical relevance, and amended versions of Arrhenius’s theorems demonstrate that there is no satisfactory population prospect axiology. These impossibility theorems do not depend on Finite Fine-Grainedness, so lexical views do not escape them. (shrink)

Advances in technology have made it possible for us to take actions that affect the numbers and identities of humans and other animals that will live in the future. Effective and inexpensive birth control, child allowances, genetic screening, safe abortion, in vitro fertilization, the education of young women, sterilization programs, environmental degradation and war all have these effects. Although it is true that a good deal of effort has been devoted to the practical side of population policy, moral theory has (...) not dealt adequately with the new possibilities. The dilemma faced by moral theory is that traditional theories cannot answer moral questions involving the creation of people. Two related problems arise. The first concerns numbers: how many people should there be? The second asks what sort of people should live and what their levels of well-being should be. Conventional social-contract theories, including the work of Rawls (1971), are restricted to situations with a fixed number of individuals. Sumner (1978) attempts to extend a Rawlsian veil-of-ignorance approach to possible people but is aware of the difficulties involved. The main problem is that possible people must be thought to benefit when they move from non-existence to existence, a view that we reject (see Section 1, Heyd, 1992, Chapter 1; McMahan, 1996a; Parfit, 1984, Appendix G). Rights-based and duty-based theories suffer from a similar problem; there must be a person who has the right or a person to whom the duty is owed (see McMahan, 1981). (shrink)

This article examines several families of population principles in the light of a set of axioms. In addition to the critical-level utilitarian, number-sensitive critical-level utilitarian, and number-dampened utilitarian families and their generalized counterparts, we consider the restricted number-dampened family and introduce two new ones: the restricted critical-level and restricted number-dependent critical-level families. Subsets of the restricted families have non-negative critical levels, avoid the `repugnant conclusion' and satisfy the axiom priority for lives worth living, but violate an important independence condition.

This thesis consists of a series of papers in population ethics: a subfield of normative ethics concerned with the distinctive issues that arise in cases where our actions can affect the identities or number of people of who ever exist. Each paper can be read independently of the others. In Chapter 1, I present a dilemma for Archimedean views in population axiology: roughly, those views on which adding enough good lives to a population can make that population better than any (...) other. In Chapter 2, I extend Gustaf Arrhenius’s famous impossibility theorems in population axiology into the domain of choices under risk. My risky impossibility theorems dispense with the assumption that welfare levels are finitely fine-grained, and so tell against lexical views in population axiology. In Chapter 3, I present objections to critical-level and critical-range views in population axiology. I then sketch out what I call the ‘Imprecise Exchange Rates View’ and argue that it is an attractive alternative. In Chapter 4, I address critical-level and critical-range views again. This time, I note that they are vulnerable to objections from biographical identity: identity between lives. I suggest that these objections give us reason to reject critical-level and critical-range views and embrace the Total View. In Chapter 5, I argue that objections of the same form – objections from personal identity – tell against person-affecting views in population ethics. In Chapter 6, I draw out some counterintuitive implications of two recent complaints-based theories of the procreation asymmetry. (shrink)